1. Field of the Invention
This invention generally relates to a siphon coffee maker or like beverage making device in which hot water in a lower container is fed to an upper container provided with a material such as coffee powder therein by making use of difference in aerial pressure in the containers and further in which the hot water is returned to the lower container to thereby extract ingredients from the material.
2. Description of the Prior Art
Siphon coffee makers of the prior art type generally comprise a lower container into which a predetermined amount of water is poured and which is heated with an alcohol lamp, an upper container provided therein with coffee powder which amount corresponds with that of the water provided in the upper container and having a water feed tube downwardly extending from the bottom thereof through a filter to be inserted into the lower container. In operation, the water in the lower container is transferred through the tube into the upper container due to increase of pressure in the lower container when heated and boiled with the alcohol lamp. Thus, the hot water is mixed with the coffee powder in the upper container. When the fire of the alcohol lamp is turned out, the aerial pressure in the lower container is decreased. The hot water mixed with coffee powder is transferred through the filter to the lower container so that coffee is gained.
It has been generally known that more flavorous coffee is gained where coffee powder to which small amount of hot water is poured is left wet for a short period of time before pouring an amount of hot water necessary for extraction. This operation is hereinafter referred to as "soak-like processing."
According to the above-described siphon coffee maker, however, when the water in the lower container is heated and boiled, all the hot water is successively fed to the upper container. Accordingly, the soak-like processing cannot be performed. Thus, the prior art siphon coffee maker has a problem to be solved in the point of flavor of coffee.
Additionally, in the prior art siphon coffee makers, the fire of the alcohol lamp or the like needs to be manually turned out so that the hot water mixed with coffee powder in the upper container is fed through the filter to the lower container. Thus, an operator is forced into troublesome manual operation. Further, the operator needs to be by the side of the coffee maker while the water in the lower container is heated. Further, the fire of the alcohol lamp needs to be timely turned out after coffee is collected in the lower container. The operation timing, however, differs from time to time and the flavor of coffee also differs from time to time.